"One of the great mysteries about North America is what killed off woolly mammoths and other exotic animals that roamed the land after the last ice age. Ideas have ranged from a comet impact and climate change to human hunters. A study published Friday in Science Magazine provides new clues about this — cleverly deduced from samples of a fungus that grew on the animals' dung."

Richard Harris reports for NPR's Morning Edition November 20, 2009. [2]